Special:CentralAuth fails too, both with that message:
Exception encountered, of type "Exception" [VyaY1ApEEaoAADZIqi4AAAAH] /w/index.php?title=Special%3ACentralAuth&target=PiRSquared Exception from line 2291 of /srv/mediawiki/php-master/extensions/CentralAuth/includes/CentralAuthUser.php: Could not find local user data for PiRSquared@eswiki Backtrace: #0 /srv/mediawiki/php-master/extensions/CentralAuth/includes/CentralAuthUser.php(2256): CentralAuthUser->localUserData(string) #1 /srv/mediawiki/php-master/extensions/CentralAuth/includes/specials/SpecialCentralAuth.php(122): CentralAuthUser->queryUnattached() #2 /srv/mediawiki/php-master/includes/specialpage/SpecialPage.php(417): SpecialCentralAuth->execute(NULL) #3 /srv/mediawiki/php-master/includes/specialpage/SpecialPageFactory.php(572): SpecialPage->run(NULL) #4 /srv/mediawiki/php-master/includes/MediaWiki.php(282): SpecialPageFactory::executePath(Title, RequestContext) #5 /srv/mediawiki/php-master/includes/MediaWiki.php(745): MediaWiki->performRequest() #6 /srv/mediawiki/php-master/includes/MediaWiki.php(519): MediaWiki->main() #7 /srv/mediawiki/php-master/index.php(43): MediaWiki->run() #8 /srv/mediawiki/w/index.php(3): include(string) #9 {main}